Water Purification & Pollution

How Water Treatment Works

https://www.youtube.com/watch?v=tuYB8nMFxQA

During our lab, what 4 steps in the water treatment process did we use?

• Aeration

• Coagulation

• Sedimentation

• Filtration

Aeration

• Gas bubbles escape• Oxygen is added

Coagulation

• Alum is added –sticks to solid particles so that they clump together and separate from water – “floc”

Sedimentation

• Gravity pulls the floc to the bottom in settling basins

Filtration

• Remaining water is filtered through sand, pebbles

What is the 5th step?

• Adding disinfectants to water to purify it and kill any organisms

How long does cardboard take to break down?

• 2 weeks

How long does it take photodegradable packaging to break down?

• 6 weeks

How long does it take newspaper to break down?

• 6 weeks

How long does it take styrofoam to break down?

• 80 years

How long does it take for aluminum to break down?

• 200 years

How long does it take plastic packaging to break down?

• 400 years

How long does it take glass to break down?

• Takes so long that we do not know fully

CHALLENGE WATER POLLUTION SCENARIOS: How do these activities lead to water

pollution?

6th Grade

Allowing Animals to graze directly next to a stream

• 1) Wastes pass disease-carrying bacteria

• 2) prevents soil from eroding, so that water does not travel faster and further

• 2) Loss of riparian vegetation • Plantlife that exists along a waterway• Benefit: absorb pollutants before they exit downstream

Fields left empty after harvesting crops

• 1) soil is looser, filled with fertilizers and pesticides, so it erodes more quickly, carrying them further

PowerPlants returning water that is not polluted into a river after using it to cool down machines

• Warm water (even if not polluted) causes many organisms to die

Having fun on a motorboat with friends

*Oil and gas to keep it moving• Harms wildlife• Hard to get out of water

*Litter can easily get into the water (marine dumping)

Driving a car down a highway

• Oil and gas spills road is impermeable, surface runoff carries it to nearby ponds/lakes/rivers

• Litter

Putting salt on the road after a snow day to make it less slippery

• Rain carries salt to freshwater sources

• Can change the LAKE TURNOVER process

• Damages plants

Using cleaning products labeled “environmentally friendly” and “biodegradable”

• Remove oxygen from the water

Using laundry detergents with phosphates in them

• Phosphates are food to algae

• Cause Eutrophication

Mercury is emitted into the air by burning coal for fuel

• Atmospheric Deposition: pollutes air, creating acid rain

• mercury poisoning